129 Words and the Weight of Worlds

We will soon cross a Rubicon in our new commercial space age. In 2024, a rocket lifted off every 36 hours. In 2025, every 28 hours. Commercial providers now account for 70% of global launches. The moment when rockets launch every 24 hours – daily space flight – will mark the crossing: the point when space flight fully transitions from extraordinary scientific achievement to routine commercial activity. This shift brings new urgency to an old question: who bears responsibility when private companies operate in space? The answer to this question turns on the 129 words that constitute Article VI of the Outer Space Treaty. In this post, I examine two competing interpretations of Article VI and argue that, despite leading to similar outcomes, the choice between these interpretations will fundamentally shape the future of international space law.

A Closer Look at Article VI

Article VI admits two different readings. Under Article VI’s traditional interpretation, States bear international responsibility for all their nationals’ space activities. As such, private space activities are much akin to government activity for the purposes of international responsibility. While this interpretation aligns with state practice, an alternative interpretation finds some support in the space law literature. This alternative interpretation posits that States will only bear international responsibility for their own national space activities – that is, the activities that can be attributed to them under the general rules of state responsibility.

To better contextualize the traditional and alternative interpretations, let’s look at the common starting point – the text itself. Given that Article VI is one great slab of text, devoid of even a single paragraph break, I break it down here into three constituent sentences. The first sentence provides that:

States Parties to the Treaty shall bear international responsibility for national activities in outer space, including the Moon and other celestial bodies, whether such activities are carried on by governmental agencies or by non-governmental entities, and for assuring that national activities are carried out in conformity with the provisions set forth in the present Treaty.

This sentence performs two functions: it establishes when international responsibility will arise and mandates conformity to the Outer Space Treaty. The second sentence reads:

The activities of non-governmental entities in outer space, including the Moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty.

This second sentence seems clear enough: States Parties must authorize and supervise non-governmental space activities. Our third and final sentence reads:

When activities are carried on in outer space, including the Moon and other celestial bodies, by an international organization, responsibility for compliance with this Treaty shall be borne both by the international organization and by the States Parties to the Treaty participating in such organization.

This third sentence addresses the specific case of space activities conducted by an international organization. Looking closer over these three sentences, we can see that Article VI uses “national activities” only once, in its first sentence. The subsequent requirements for authorization and supervision in the second sentence, and the third sentence’s clarification concerning international organizations, refer simply to “activities.” Was this differentiation deliberate? Or is it just poor drafting?

The latter explanation is plausible. The Outer Space Treaty is hardly a monument to precision. Case in point: Article VI refers to “international organizations” while Article XIII specifies “international intergovernmental organizations.” Was a difference intended by adding “intergovernmental”? Surely not. This is a distinction without a difference. Could it be that the varying use of “national” within Article VI is similarly accidental? That the omission of “national” from the second and third sentences in Article VI was a mere slip of the pen?

An alternative take might be that, given the stakes involved, the omission of “national” from the second and third sentences reflects a deliberate ambiguity that allowed the Cold War superpowers – the United States and the Soviet Union – to sign the same text while reading it differently. But what exactly are “national activities”? Following the traditional interpretation, “national activities” means activities by a State Party’s nationals. On this basis, some government somewhere bears direct international responsibility for every satellite, every lunar lander, every spacewalk – a framework increasingly tested as commercial launch rates multiply.

The Soviet Perspective

To begin to answer some of these questions, I turn to Article VI’s history. As related in 1967 (p. 437) by Paul G. Dembling and Daniel M. Arons:

Article VI was taken almost verbatim from Article VI of the Soviet draft [of the Outer Space Treaty] … [t]he United States draft contained no comparable provision but the United States delegate readily acceded to the Soviet version subject to changing the term “nongovernmental bodies corporate” to “nongovernmental entities,” the word “corporate” not being adequately descriptive. When the Soviet delegate accepted this minor change, debate ended on the first two sentences of Article VI.

Dembling and Arons were, at that time, the General Counsel and an Attorney-Advisor at NASA, respectively. They enjoyed front-row seats as the Outer Space Treaty was being hashed out at the international level, and as it worked its way through the American ratification process. Yet their account of Article VI’s history suggests the prime relevance of the Soviet perspective. It was, after all, the Soviet delegates who were ‘holding the pen’ vis-à-vis Article VI. And the Soviet perspective on Article VI was clear, and in-line with the Soviet theory of “peaceful coexistence.” As Gennady Zhukov and Yuri Kolosov state in the English translation of their Soviet monograph International Space Law (p. 65):

If any state, by virtue of the social features of its structure, permits private companies to operate in space, that is its internal affair. What is important for international cooperation is that it should develop on the level of relations between states and not on the level of relations between states and private businessmen. It is for that reason that the [Outer] Space Treaty provides for the international responsibility of states for all types of national activities in space, irrespective of whether these activities are conducted by governmental agencies or by non-governmental organizations. If private companies are permitted to operate in space – as is the case, say, in the USA and Japan – international responsibility for all activities in space nevertheless rests entirely with the state in this case as well.

Clearly, the Soviet perspective informed the traditional interpretation. This irony is not lost on Charles Stotler in his recent contribution to the Chicago Journal of International Law. After all, the orthodoxy of the traditional interpretation means that the Soviet Union – which originally wanted to ban private space activities entirely – achieved a (posthumous) victory. Without changing America’s constitutional system, the Outer Space Treaty converted every American private space venture into a de facto government activity, at least for purposes of international responsibility. Khrushchev’s last laugh, as it were.

Challenging Orthodoxy

Curtis Schmeichel, in his 2010 monograph State Responsibility for Non-Governmental Entities in Outer Space, raises a fundamental objection to the traditional interpretation: that it is unsupported by the rules of treaty interpretation. Working methodically through the Vienna Convention on the Law of Treaties, Schmeichel argues that the phrase “national activities” in Article VI simply means “activities of the nation” (p. 39). As such, the phrase does not cover the mere space activities of nationals. Rather, those activities must be attributable to a State under international law in order to be the “national activities” of that State. Consideration of Article II of the Outer Space Treaty may reinforce this interpretation, as the usage of “national appropriation” there is often viewed as precluding State acquisition of territory in outer space, rather than addressing actions of a State’s nationals per se.

Steven Bartz’s novel and insightful analysis in the Journal of Air Law and Commerce builds upon Schmeichel’s critique. He emphasizes how the provision’s structure – with “national activities” appearing only once – suggests different scopes for different obligations. States bear responsibility for genuinely national (governmental) activities, while their duties regarding private activities are purely procedural (that is, to authorize and supervise). Crucially, the conformity obligation in Article VI’s first sentence only extends to “national activities.” So, if Schmeichel and Bartz are correct, then the Outer Space Treaty’s requirement that activities conform to its provisions does not apply to purely private activities.

Theory Meets Practice

These challenges to orthodoxy sustain and enliven the Article VI debate. The debate is fueled, no doubt, by a fact noted by Stotler: following the same Vienna Convention rules, reading the same histories and travaux préparatoires, reasonable lawyers can reach opposite conclusions regarding Article VI. In other words, both the traditional and alternative interpretations are legally arguable. However, adopting Schmeichel and Bartz’s interpretation entails the creation of a loophole in the Treaty regime: if there is no obligation to ensure that all space activities conform to the Outer Space Treaty, then States must assure only that attributable space activities conform. Non-attributable space activities – that is, purely private space activities – may not need to conform to the Outer Space Treaty at all. In a policy brief, the Canadian Government notes that “[n]on-state actors have started to overshadow state actors and now lead over 70% of space activities” (p .1). As such, the Treaty risks governing only a shrinking minority of space activities – namely, military satellites and scientific missions.

The existence of such a loophole is anathema to many. Yet I suggest here that both interpretations are likely to yield similar outcomes in practice. Even under the alternative interpretation, States Parties cannot lawfully authorize a non-governmental entity to do something that States Parties are themselves prohibited from doing under the Treaty. And the continuing supervision obligation means States Parties should detect non-conforming space activities – or face the allegation that they failed to supervise. Further, the acts of authorization and supervision themselves could lead to attribution under international law. So, a State Party that authorizes an arms manufacturer to test weapons on the Moon (an activity specifically prohibited under Article IV of the Outer Space Treaty), or fails to detect such testing, may well bear responsibility, regardless of whether we read Article VI according to the traditional or alternative interpretation.

Converging Paths

While the result may be the same, the path taken still matters. As we approach the Rubicon of daily launches, Article VI’s 129 words will determine whether space law evolves through sovereign decisions or commercial competition. The traditional interpretation fosters what M.J. Durkee calls “attributed lawmaking” (p. 428). Durkee argues that

[b]ecause private missions are defined by the Outer Space [T]reaty as “national” missions, which are attributed to the home nation and for which home nations are responsible, these private acts can also be attributed to those nations for the purposes of customary law formation and treaty interpretation. This is because when a corporation whose activity is attributed to the state publicly asserts a legal rule and acts on it, and a nation does nothing, that nation implicitly accepts the corporate rule.

Conversely, the alternative interpretation emphasizes that responsibility will flow via authorization or supervision. But even if both paths may result in conformity to the Outer Space Treaty, the path chosen will frame our thinking about the accretion of norms in space law – in short, who makes the rules as businesses expand into outer space. Seen in that light, these 129 words may well carry the weight of worlds.